The present invention relates to processes and systems enabling blind or partially sighted subjects to find their bearings, without the assistance of a third person, in a completely unfamiliar environment, particularly in a building or in a street.
How can a blind or partially sighted subject be given the same autonomy as a sighted subject xe2x80x9cdiscoveringxe2x80x9d a place they have never been before for the first time? This is the problem related to the present invention. This problem is particularly difficult to solve since the blind or partially sighted subject does not have any material bearing that could be remembered or recognised through touch. People are surprised by the idea that a blind subject could enjoy the same degrees of freedom as a sighted subject in an unknown place. The present invention, by placing sighted and blind or partially sighted subjects at the same level, overcomes a taboo.
Processes and systems using GPS (Global Positioning System) techniques to determine a subject""s position are known. Such techniques are envisaged to enable blind or partially sighted subjects to find out their position in an unknown place and determine their route in relation to the obstacles on their path. This solution is not satisfactory for locations (particularly building or underground transport system passages) where GPS satellite links are not functional.
The process according to the invention enables blind or partially sighted subjects to find their bearings and way in an unknown environment, avoiding obstacles. Said process consists of remotely informing the blind or partially sighted subject of the path to follow, to move from one point to another, by means of a portable sensor, particularly of the tactile or audio type, receiving information from local transmitters.
In a first embodiment, said process comprises the following steps consisting of:
positioning along the path followed by the blind or partially sighted subject a plurality of local micro-transmitters particularly in the form of transmitting chips,
transmitting, by means of the transmitting chips, bearing information concerning the path to follow to reach the destination selected by the blind or partially sighted subject.
The blind or partially sighted subject is provided with a portable object. Said portable object makes it possible to implement the following steps of the process according to the invention:
the step consisting of determining the direction of movement of the blind or partially sighted subject with reference to a bearing, particularly the magnetic north,
the step consisting of selecting a destination,
the step consisting of receiving the bearing information transmitted by the transmitting chips concerning the path to follow to reach the selected destination,
the step consisting of calculating the direction to follow according to the direction of the bearing, the selected destination and the bearing information received concerning the path to follow,
the step consisting of transmitting the direction to follow to the blind or partially sighted subject, particularly using audio signals or tactile information.
In a second embodiment, said process consists of providing the blind or partially sighted subject with a portable object, interacting with the ground and/or obstacles in the vicinity, making it possible to:
determine the reference distance of the portable object with reference to the ground,
calculate the distance, with reference to the portable object, of an obstacle located on the blind or partially sighted subject""s path,
compare the distance of the obstacle to the reference distance and detect hollow obstacles and/or raised surface obstacles,
transmit the topographical characteristics of the obstacle on his/her path to the blind or partially sighted subject, particularly using tactile information.
The invention also relates to a system enabling blind or partially sighted subjects to find their bearings and way in an unknown environment, avoiding obstacles. Said system comprises means to remotely inform the blind or partially sighted subject of the path to follow, to move from one point to another, by means of a portable sensor, particularly of the tactile or audio type, receiving information from local transmitters.
In a first embodiment, said system comprises a plurality of micro-transmitters, particularly in the form of chips positioned along the path to be followed by blind or partially sighted subjects. Said chips comprise:
a memory containing bearing information concerning their position and the path to follow, and
transmission means to transmit said bearing information.
The system also comprises a portable object provided to blind or partially sighted subjects. Said portable object comprises:
means to receive the information transmitted by the micro-transmitters,
means to select a destination,
calculation means to calculate:
the direction of movement of blind or partially sighted subjects with reference to the direction of a bearing, particularly a compass,
the direction to follow according to the direction of the bearing, the selected destination and the information transmitted by the micro-transmitters,
means for transmitting the direction to follow to blind or partially sighted subjects, particularly tactile means or audio means.
The micro-transmitters are autonomous and programmed according to their position.
Preferably, the micro-transmitters are not powered. Advantageously, the portable object comprises means to create and radiate an electromagnetic field. The micro-transmitters receive their electrical energy from the electromagnetic field created by the portable object.
In a second embodiment, said system comprises a portable object provided to the blind or partially sighted subject. Said portable object comprises calculation means:
to calculate the reference distance of the portable object with reference to the ground,
to calculate the distance, with reference to the portable object, of an obstacle located on the blind or partially sighted subject""s path.
Said portable object also comprises:
means to compare the distance of the obstacle to the reference distance and detect hollow obstacles and/or raised surface obstacles,
means to transmit the topographical characteristics of the obstacle on his/her path to the blind or partially sighted subject, particularly using tactile information.
The invention also relates to a portable object intended to implement the system described above.
The invention also relates to a micro-transmitter intended to implement the system described above.